Specially designed for motorcycle engines, this low-volume Colortune maintains the engine�s compression ratio, ensuring better firing of the mixture. Simple to use, the Colortune spark plug features a glass insulator viewing window, making the combustion flame visible. The kit also includes a view scope with an adjustable mirror, allowing the flame to be seen where engine access is restricted. The flame colour inside the cylinder shows the richness of the air-fuel ratio: a yellow flame indicates a rich mixture, a bluish-white flame a weak mixture, while a Bunsen blue flame is usually correct. By adjusting the mixture screw to achieve the correct flame colour, the engine can be tuned accurately. This Gunson Colortune kit for motorcycles is designed for use with a 12mm spark plug size. Sadly.
